The invention relates generally to the field of power generation and more particularly to a power generation system utilizing waste heat from a reformer system.
Gas engine plants typically control emissions such as nitrogen oxide (NOx) from the exhaust stream of an internal combustion engine by reforming fuel exhaust gas after treatment. An alternative approach is to limit NOx formation by further increasing the air-fuel ratio of the charge. As such lean mixtures burn unstable, this approach is requiring a fuel with specific combustion behavior which can, for instance, be generated in an upstream fuel reforming process.
A reformer system converts a portion of liquid or gaseous fuels to a synthesis gas (or syngas), usually by a catalytic fuel conversion processes. The syngas is rich in hydrogen and can be further mixed with gaseous fuels to form a hydrogen-rich combustion gas before being fed to the internal combustion engine. This hydrogen-rich combustion gas allows for a stable and lean combustion, thereby reducing NOx emissions.
The reformer system involves high temperature (exothermal) processes to generate the syngas at elevated temperatures. Generally, before using the syngas in the internal combustion engine, the syngas is required to be cooled to a temperature according to typical interface conditions in the gas engine plant.
Cooling of the syngas in reformer systems leads to waste heat which is conventionally released into the ambient atmosphere.